Interrupted Time-Series Analysis of Regulations to Reduce Paracetamol (Acetaminophen) Poisoning

BACKGROUND: Paracetamol (acetaminophen) poisoning is the leading cause of acute liver failure in Great Britain and the United States. Successful interventions to reduced harm from paracetamol poisoning are needed. To achieve this, the government of the United Kingdom introduced legislation in 1998 limiting the pack size of paracetamol sold in shops. Several studies have reported recent decreases in fatal poisonings involving paracetamol. We use interrupted time-series analysis to evaluate whether the recent fall in the number of paracetamol deaths is different to trends in fatal poisoning involving aspirin, paracetamol compounds, antidepressants, or nondrug poisoning suicide. METHODS AND FINDINGS: We calculated directly age-standardised mortality rates for paracetamol poisoning in England and Wales from 1993 to 2004. We used an ordinary least-squares regression model divided into pre- and postintervention segments at 1999. The model included a term for autocorrelation within the time series. We tested for changes in the level and slope between the pre- and postintervention segments. To assess whether observed changes in the time series were unique to paracetamol, we compared against poisoning deaths involving compound paracetamol (not covered by the regulations), aspirin, antidepressants, and nonpoisoning suicide deaths. We did this comparison by calculating a ratio of each comparison series with paracetamol and applying a segmented regression model to the ratios. No change in the ratio level or slope indicated no difference compared to the control series. There were about 2,200 deaths involving paracetamol. The age-standardised mortality rate rose from 8.1 per million in 1993 to 8.8 per million in 1997, subsequently falling to about 5.3 per million in 2004. After the regulations were introduced, deaths dropped by 2.69 per million (p = 0.003). Trends in the age-standardised mortality rate for paracetamol compounds, aspirin, and antidepressants were broadly similar to paracetamol, increasing until 1997 and then declining. Nondrug poisoning suicide also declined during the study period, but was highest in 1993. The segmented regression models showed that the age-standardised mortality rate for compound paracetamol dropped less after the regulations (p = 0.012) but declined more rapidly afterward (p = 0.031). However, age-standardised rates for aspirin and antidepressants fell in a similar way to paracetamol after the regulations. Nondrug poisoning suicide declined at a similar rate to paracetamol after the regulations were introduced. CONCLUSIONS: Introduction of regulations to limit availability of paracetamol coincided with a decrease in paracetamol-poisoning mortality. However, fatal poisoning involving aspirin, antidepressants, and to a lesser degree, paracetamol compounds, also showed similar trends. This raises the question whether the decline in paracetamol deaths was due to the regulations or was part of a wider trend in decreasing drug-poisoning mortality. We found little evidence to support the hypothesis that the 1998 regulations limiting pack size resulted in a greater reduction in poisoning deaths involving paracetamol than occurred for other drugs or nondrug poisoning suicide

Dietary supplementation with ferric tyrosine improves zootechnical performance and reduces caecal Campylobacter spp. load in poultry

The objective of this study was to evaluate the effect of ferric tyrosine on the reduction of Campylobacter spp. and zootechnical performance in broilers exposed to Campylobacter spp. using a natural challenge model to simulate commercial conditions. Additionally, the minimum inhibitory concentrations (MIC) of ferric tyrosine against common enteropathogens were evaluated. On day 0, 840 healthy male day-old birds (Ross 308) were randomly allocated to 6 replicate pens of 35 birds and fed diets containing different concentrations of ferric tyrosine (0, 0.02, 0.05 and 0.2 g/kg) in mash form for 42 days. Overall, broilers fed diets containing ferric tyrosine showed significantly improved body weight at day 42 and weight gain compared to the control group. However, birds fed ferric tyrosine ate significantly more than the control birds so significant improvements in FCR were not observed. Microbiological analyses of caecal samples collected on day 42 of the study showed, per gram sample, 2-3 log10 reduction in Campylobacter spp. and 1 log10 reduction in Escherichia coli in the groups fed diets containing ferric tyrosine compared to the control and Salmonella enterica, indicating that ferric tyrosine does not exert antimicrobial activity. Collectively, these results show that birds fed ferric tyrosine grew faster and consumed more feed compared to the control birds indicating potential benefits of faster attainment of slaughter weight with no significant reduction on feed efficiency. Moreover, ferric tyrosine significantly reduces caecal Campylobacter spp. and E. coli indicating potential as a non-antibiotic feed additive to lower the risk of Campylobacter infections transmitted through the food chain

Cross-Sector Review of Drivers and Available 3Rs Approaches for Acute Systemic Toxicity Testing

Acute systemic toxicity studies are carried out in many sectors in which synthetic chemicals are manufactured or used and are among the most criticized of all toxicology tests on both scientific and ethical grounds. A review of the drivers for acute toxicity testing within the pharmaceutical industry led to a paradigm shift whereby in vivo acute toxicity data are no longer routinely required in advance of human clinical trials. Based on this experience, the following review was undertaken to identify (1) regulatory and scientific drivers for acute toxicity testing in other industrial sectors, (2) activities aimed at replacing, reducing, or refining the use of animals, and (3) recommendations for future work in this area

EFSA BIOHAZ Panel (EFSA Panel on Biologicial Hazards), 2013. Scientific Opinion on the public health hazards to be covered by inspection of meat (solipeds)

A risk ranking process identified Trichinella spp. as the most relevant biological hazard in the context of meat inspection of domestic solipeds. Without a full and reliable soliped traceability system, it is considered that either testing all slaughtered solipeds for Trichinella spp., or inactivation meat treatments (heat or irradiation) should be used to maintain the current level of safety. With regard to general aspects of current meat inspection practices, the use of manual techniques during current post-mortem soliped meat inspection may increase microbial cross-contamination, and is considered to have a detrimental effect on the microbiological status of soliped carcass meat. Therefore, the use of visual-only inspection is suggested for “non-suspect” solipeds. For chemical hazards, phenylbutazone and cadmium were ranked as being of high potential concern. Monitoring programmes for chemical hazards should be more flexible and based on the risk of occurrence, taking into account Food Chain Information (FCI), covering the specific on-farm environmental conditions and individual animal treatments, and the ranking of chemical substances, which should be regularly updated and include new hazards. Sampling, testing and intervention protocols for chemical hazards should be better integrated and should focus particularly on cadmium, phenylbutazone and priority “essential substances” approved for treatment of equine animals. Implementation and enforcement of a more robust and reliable identification system throughout the European Union is needed to improve traceability of domestic solipeds. Meat inspection is recognised as a valuable tool for surveillance and monitoring of animal health and welfare conditions. If visual only post-mortem inspection is implemented for routine slaughter, a reduction in the detection of strangles and mild cases of rhodococcosis would occur. However, this was considered unlikely to affect the overall surveillance of both diseases. Improvement of FCI and traceability were considered as not having a negative effect on animal health and welfare surveillance

The Women's international study of long-duration oestrogen after menopause (WISDOM): a randomised controlled trial

BACKGROUND: At the time of feasibility work and final design of the trial there was no randomised control trial evidence for the long-term risks and benefits of hormone replacement therapy. Observational studies had suggested that long term use of estrogen was likely to be associated, amongst other things, with reduced risks of osteoporosis and ischaemic heart disease and increased risks of breast and endometrial cancer. Concomitant use of progestogens had been shown to protect against endometrial cancer, but there were few data showing how progestogen might affect estrogen actions on other conditions. Disease specific risks from observational studies suggested that, overall, long-term HRT was likely to be beneficial. Several studies showed that mortality from all causes was lower in HRT users than in non-users. Some secondary cardiovascular prevention trials were ongoing but evidence was also required for a range of outcomes in healthy women. The WISDOM trial was designed to compare combined estrogen and progestogen versus placebo, and estrogen alone versus combined estrogen and progestogen. During the development of WISDOM the Women's Health Initiative trial was designed, funded and started in the US. DESIGN: Randomised, placebo, controlled, trial. METHODS: The trial was set in general practices in the UK (384), Australia (94), and New Zealand (24). In these practices 284175 women aged 50–69 years were registered with 226282 potentially eligible. We sought to randomise 22300 postmenopausal women aged 50 – 69 and treat for ten years. The interventions were: conjugated equine estrogens, 0.625 mg orally daily; conjugated equine estrogens plus medroxyprogesterone acetate 2.5/5.0 mg orally daily; matched placebo. Primary outcome measures were: major cardiovascular disease, osteoporotic fractures, breast cancer and dementia. Secondary outcomes were: other cancers, all cause death, venous thromboembolism and cerebro-vascular disease. RESULTS: The trial was prematurely closed during recruitment following publication of early results from the Women's Health Initiative. At the time of closure, 56583 had been screened, 8980 entered run-in, and 5694 (26% of target of 22,300) randomised. Those women randomised had received a mean of one year of therapy, mean age was 62.8 years and total follow-up time was 6491 person years. DISCUSSION: The WISDOM experience leads to some simple messages. The larger a trial is the more simple it needs to be to ensure cost effective and timely delivery. When a trial is very costly and beyond the resources of one country, funders and investigators should make every effort to develop international collaboration with joint funding

Surveillance of a recently switched non-prescription medicine (diclofenac) using a pharmacy-based approach

Purpose - Postmarketing surveillance of prescription medicines is a routine practice, yet similar evaluation of non-prescription medicines, including those recently switched from prescription status, is uncommon. This study presents the methodologic issues and limitations of the use of pharmacies in the 'post-reclassification' surveillance of oral diclofenac potassium 25 mg which had been recently switched from physician prescription to non-prescription sale. Methods - Consenting user-purchasers were recruited from 175 New Zealand pharmacies over 4 months. Purchasers were mailed a questionnaire for completion 7 days post-purchase. Those purchasers who met criteria for being potentially 'at risk' of adverse events were re-surveyed 30 days post-purchase. A descriptive analysis was carried out using t-test and chi-square as appropriate. These results were compared to those from other types of studies in this area. Results - The 1240 recruited purchasers returned 990 valid questionnaires (80% response). Of these 557 (56%) met 'at risk' criteria and received the second questionnaire with 480 valid returns (86.2% response). Conclusions - Useful data was gathered on the 'real-life' usage of a medicine recently reclassified from prescription to non-prescription sale. The use of community pharmacies as recruiting centres was found to be effective. Copyright (C) 2000 John Wiley and Sons, Ltd